Laser cutting of corrugated boards

Corrugated board converting industry usually uses high-capacity machines but nowadays customers may want even smaller and smaller series. Small series is not anymore economical with punching knifes, because tool cost is quite high compared to cost of one piece. Conventionally cutting of corrugated board is done by mechanical cutting. Making of these punching knifes is time consuming and they also wear out after large number of punches. Laser could be the solution for cutting small series production and also for fast delivery needs. Laser cutting of corrugated board is possible and cut quality is very good. The most important advantage of laser technology is the flexibility: the batch size can be, ten pieces or ten thousand pieces or even one piece. Changing of the cutting geometry is only a question of programming. In this study two different corrugated boards were cut with laser in Lappeenranta Laser Processing Centre (LLPC). The laser equipment used in these studies was 2.7 kW CO2-laser. The cutting speed 100 m/min was achieved with laser power of 700 W when 1 mm thick corrugated board was cut straight with laser. Laser cutting of corrugated boards was possible and laser power was linearly dependent on cutting speed. Smoke formation was fairly abundant. Cut parts smell quite badly right after cutting but odour disappears within few days in open air. Despite of this the quality of cut of corrugated boards with thickness of 1 and 3 mm was good. In this paper is also one small series production batch of 10 pieces was cut with laser and calculations of the economics of cutting were made. Economics are compared to punching knifes and it seems that with this kind of product laser has the advantage.